The invention relates to a method of cutting at least one thin section from a sample block that is arranged in a cassette and tagging at least one specimen slide such that it can be allocated to the specific sample block from which the thin section has been cut. For this method an apparatus is used for identifying the at least one specimen slide. The apparatus has at least one reading unit for reading a machine-readable coded information of a cassette identifier of a cassette, and at least one tagging unit for generating an at least machine-readable coded information for identifying the specimen slide. Identification of the specimen slide is accomplished with a specimen slide identifier dependent on the cassette identifier sensed with the aid of the reading unit. The invention further relates to a method for identifying at least one specimen slide.
The apparatus and the method are preferably used in histological technology. In histological technology, tissue samples that were taken from a patient are investigated. For this, the tissue samples are firstly embedded into an embedding medium, preferably paraffin. A hardened paraffin block produced in this fashion, having the tissue sample, is also referred to as a sample block. The sample blocks are each arranged in a cassette, and are transported and processed in that cassette. For unique identifiability of the sample blocks, the cassettes each have a unique identifier. The sample blocks are preferably delivered to a microtome, in which thin sections of the sample blocks are produced. The thin sections are each mounted onto a specimen slide, stained, and covered with a coverslipping agent and a coverslip. The specimens are then delivered for further investigations to at least one further apparatus, in particular to a microscope.
The tissue samples, and thus also the thin sections that are produced, must be uniquely identifiable throughout all the processing steps that have been described. The intention thereby is to preclude confusion between the samples in order to prevent incorrect allocation of a sample, a thin section, or an investigation result. An incorrect allocation can cause a healthy patient to be considered ill, and an ill patient to be erroneously considered healthy. Medical actions that might be necessary are then omitted or are instituted only after a delay. Unique identification further serves to avoid sample losses, and to relocate samples that have been lost. In order to ensure unique identifiability of the samples during the entire processing procedure, the specimen slides onto which the thin slides of the tissue samples are mounted are equipped with a unique identifier. The two methods explained below are, in particular, conceivable for this:
In the first possible method, the cassettes rest individually on a cooling plate. Upon insertion of a cassette into a microtome, the identifier of the cassette is read out. As a function of that identifier, at least one specimen slide is manually labeled. Such manual labeling is susceptible to error by its very nature. In addition, such manual labeling is time- and cost-intensive. Manual identification of the specimen slides is particularly critical when the specimen slides must be read by other persons in the context of later method steps, since confusion can easily occur if the handwriting is unclear.
In a second possible method, the specimen slides are already identified before the cassettes are delivered to the microtome. The identified specimen slides, and the cassettes having the tissue samples, are transported individually to the microtome. Once one or more thin sections have been produced from a tissue sample with the aid of a microtome, the pre-identified specimen slides belonging to the cassette having the microtomed sample block must then be laboriously searched for manually, and identified by manual comparison of the identifier. This in turn carries the risk of confusion, and is moreover time- and cost-intensive.
Also known, from the document DE 101 54 843 A1, are a method and an apparatus for identifying specimen slides of microtomed tissue samples, and for processing them. In the method, an identifying information belonging to a slide is automatically sensed while it is being arranged in a microtome, and an identifier allocated thereto is automatically transferred onto at least one specimen slide. At the point in time at which a microtomed tissue sample must be mounted onto a specimen slide, only that specimen slide which is equipped with the identifier is presented at the microtome workstation. The apparatus described comprises a microtome and an identifying device arranged next to the microtome. The slides having the tissue samples to be microtomed are delivered individually to the microtome. The apparatus is disadvantageous in that clarity and the level of organization at the workstation are limited by the individual delivery of the slides having the tissue sample, thereby increasing the probability of error.
The document DE 198 41 554 A1 discloses an apparatus for receiving solid or liquid sample material, in which a coding fixedly joined to the apparatus, and/or a memory element, are provided. The codings, or the codes stored in the memory elements, are different for any two apparatuses.